A Geostationary Optical Seismometer, Proof of Concept
Abstract
We discuss the possibility of imaging the propagation of seismic waves from a very large space-based optical telescope. Images of seismic waves propagating at the Earth's surface would be an invaluable source of information for investigating earthquake physics and the effect of the subsurface on earthquake ground motions. This application would require ground displacement measurements at about every 100 m, with centimetric accuracy, and temporal sampling on the order of 1 Hz. A large field of view (> 10^5 km^2) is required to measure the full extent of a large earthquake in the areas of interest. A geostationary optical telescope with a large aperture appears to be the most promising system. We establish preliminary technical requirements for such a system, which lead us to consider a telescope with an angular field of view of 0.8° and with an aperture greater than 4 m. We discuss and quantify the various sources of noise that would limit such a system: atmospheric turbulence, evolution of ground reflectance and solar incidence angle, and stability of the platform at 1 Hz. We present numerical simulations, which account for these sources of noise. They show that key details of the seismic wave field, hardly detectable using ground-based instruments, would indeed be imaged by such a system. At the upper limit of modern technology, data flow would be about 20–50 Gb · s^(−1), and data memory would be about 50 Tb.
Additional Information
© 2012 IEEE. Manuscript received October 25, 2011; revised February 8, 2012; accepted April 15, 2012. Date of publication July 10, 2012; date of current version December 19, 2012. Part of this work was supported by the French Centre National des Etudes Spatiales and funded through the TOSCA program. Part of this work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration, and funded through the internal Research and Technology Development. The authors would like to thank M. M. Colavita of the Jet Propulsion Laboratory for the detailed and very helpful comments about turbulence. This study is the outcome of a study funded by the Keck Institute for Spaces Studies at Caltech.Additional details
- Eprint ID
- 65497
- DOI
- 10.1109/TGRS.2012.2201487
- Resolver ID
- CaltechAUTHORS:20160318-162707037
- Centre National d'Études Spatiales (CNES)
- NASA/JPL/Caltech
- JPL Research and Technology Development Fund
- Keck Institute for Space Studies (KISS)
- Created
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2016-03-18Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field
- Caltech groups
- Keck Institute for Space Studies, Seismological Laboratory, Division of Geological and Planetary Sciences